The Volume Spread Analysis (VSA) methodology focus at the relationship between price, spread, and volume, trying to identify the variations that the price of an asset may have bar by bar, candle by candle.
This indicator is based on calculates on the average volume of the bars in a close environment, that indicates when the volume is Ultrahigh, Very high , High , Normal and low.
The configuration setted is based on personal study. You can configurate the volume ratios per level, and try different results.
The indicator colors the volume bars and candles according to the volume traded.
Base colors configuration is a kind of heat map (don't forget to check the option to paint candles), but you can customize it as you wish.
Good Luck!